a-a a-b a-c a-z aaa aab aac aah aan aaz ab- aba abb abc abh abn abz ac- aca acb acc ach acn acz aha ahb ahc ahh ahn ahz an- ana anb anc anh ann anz az- aza azb azn azz baa bab bac bah ban baz bba bbb bbc bbh bbn bca bcb bcc bch bcn bcz bha bhb bhc bhh bna bnb bnc bnn bnz bza bzh bzn bzz c-- caa cab cac cah can caz cba cbb cbc cbh cbn cbz cca ccb ccc cch ccn ccz ch- cha chb chc chh chn chz cn- cna cnb cnc cnh cnn cz- czc haa hab hac hah han haz hba hbb hbc hbh hbn hbz hca hcb hcc hch hcn hha hhb hhc hhh hhn hhz hna hnb hnc hnh hnn hnz naa nab nac nah nan naz nba nbb nbc nbn nca ncb ncc nch ncn nha nhb nhc nhh nhn nhz nna nnb nnc nnh nnn nnz nzb nzz zaa zab zac zah zan zaz zbb zbc zha zhc znc znn zzz